Power supply apparatuses are essential for many electronic appliances such as personal computers, industrial computers, servers, communication products or network products. Normally, the power supply apparatus may provide stable electricity to the electronic appliance. In a case that the power supply apparatus has a breakdown, the electronic appliance is possibly damaged or the data stored in the electronic appliance is lost. For enhancing capacity and reliability of power supply, a redundant power supply system has been proposed. The redundant power supply system includes a plurality of separated power supply apparatuses, which are electrically coupled to each other and contained in a system cabinet. During operation of the redundant power supply system, individual power supply apparatuses share responsibility for providing electricity to the electronic appliance. If one of the power supply apparatuses has a breakdown and fails to normally provide electricity, the others could continuously provide electricity to the loads.
Referring to FIG. 1, a schematic exploded view of a conventional redundant power supply system is illustrated. The redundant power supply system 1 principally includes a system cabinet 10, a first power supply apparatus 11 and a second power supply apparatus 12. The system cabinet 10 includes a first receptacle 102 and a second receptacle 103, which are separated by a partition plate 101. The first power supply apparatus 11 and the second power supply apparatus 12 are accommodated within the first receptacle 102 and the second receptacle 103, respectively. The redundant power supply system 1 further includes a backside plate 13 inside the system cabinet 10. A first insertion slot 131 and a second insertion slot 132 are disposed on the backside plate 13. A first power connection interface 111 of the first power supply apparatus 11 and a second power connection interface 121 of the second power supply apparatus 12 are respectively inserted into the first insertion slot 131 and the second insertion slot 132 so as to be electrically connected to the backside plate 13. A power cable 14 is extended from the outer surface of the backside plate 13, so that the electricity provided by the redundant power supply system 1 is transmitted to an electronic appliance via the power cable 14.
Please refer to FIG. 2, which is a schematic perspective view illustrating the first power connection interface of the first power supply apparatus shown in FIG. 1. The configuration of the second power connection interface 121 of the second power supply apparatus 12 is substantially identical to that of the first power connection interface 111 of the first power supply apparatus 11. For clarification and brevity, only the first power connection interface 111 of the first power supply apparatus 11 is described. As shown in FIG. 2, an edge region 1120 of a circuit board 112 is extended externally from the casing of the first power supply apparatus 11. The first power connection interface 111 is formed on the edge region 1120 of the circuit board 112, and principally includes plural trace portions 113. Generally, the trace portions 113 includes a first trace portion 1131, a second trace portion 1132, a third trace portion 1133 and a fourth trace portion 1134. The first trace portion 1131 is used for transmitting a DC voltage. The second trace portion 1132 and the third trace portion 1133 are used for transmitting an AC voltage. The fourth trace portion 1134 is used as an earth wire. The first trace portion 1131 includes several trace wires, which are discretely arranged at regular intervals on both surfaces 1121 and 1122 of the edge region 1120 of the circuit board 112. The second trace portion 1132 and the third trace portion 1133 are arranged on the same surface of the edge region 1120, e.g. the first surface 1121 of the edge region 1120. For example, the second trace portion 1132 and the third trace portion 1133 are a neutral wire and a live wire, respectively. When the first power supply apparatus 11 is accommodated within the system cabinet 10, the AC voltage is inputted into the power converting circuit of the first power supply apparatus 11 through the second trace portion 1132 and the third trace portion 1133, and the AC voltage is converted by the power converting circuit into a regulated DC voltage. The regulated DC voltage is outputted to power an external electronic appliance through the first trace portion 1131.
For safety regulations of avoiding short-circuit occurrence in the trace portions 113, the trace wires of the trace portions 113 should be discretely arranged at regular intervals. For example, there is at least a first safety interval d1 between every two adjacent trace wires of the first trace portion 1131. There is at least a second safety interval d2 between the second trace portion 1132 and the third trace portion 1133. In addition, there is at least a third safety interval d3 between the first trace portion 1131 and the second trace portion 1132. Generally, the third safety interval d3 is greater than the second safety interval d2, and the second safety interval d2 is greater than the first safety interval d1. Since the second trace portion 1132 and the third trace portion 1133 are arranged on the same surface of the edge region 1120, the second trace portion 1132 and the third trace portion 1133 occupy much area of the first surface 1121. In addition, it is necessary to reserve specific area on the edge region 1120 of the circuit board 112 for maintaining the safety interval between the second trace portion 1132 and the third trace portion 1133. Assuming that the width of the edge region 1120 of the circuit board 112 is constant, the number of trace wires of the first trace portion 1131 is limited due to such arrangement of the second trace portion 1132 and the third trace portion 1133. In addition, the reduced number of trace wires of the first trace portion 1131 may transmit insufficient electricity through the first power connection interface 111.
In views of the above-described disadvantages resulted from the conventional method, the applicant keeps on carving unflaggingly to develop an electronic device having a power connection interface according to the present invention through wholehearted experience and research